Safety cap for extension cord sets



June 18, 1968 F. w. SCHWARTZ 3,389,367

SAFETY CAP FOR EXTENSION CORD SETS Filed March 25, 1966 INVENTORFREDERICK W. SCHWARTZ BY I AT TOiEY United States Patent "ice 3,389,367SAFETY CAP FOR EXTENSION CORD SETS Frederick W. Schwartz, Providence,R.I., assignor to Cable Electric Products, Inc., Providence, R.I., acorporation of Rhode Island Filed Mar. 25, 1966, Ser. No. 537,461 4Claims. (Cl. 339-38) ABSTRACT OF THE DISCLOSURE A safety cap for anextension cord comprising a plurality of flat rectangular portionsintegrally connected by flexible webs. The central portion is providedwith a restricted slot for receiving the extension cord to mount thesafety cap. The outer portions are provided with spaced parallel flattabs which enter the slotsin the electrical tap to be frictionallyretained therein and to dielectrically close the slots.

My present invention relates to electrical cords and terminals and moreparticularly to a novel safety cap for an extension cord.

The principal object of the present invention is to pro vide a safetycap for a multiple outlet terminal on an electrical extension cord.

A further object of the present invention is to provide a simple devicemounted on the terminal cord for plugging one or both of the freeoutlets on a multiple outlet cord.

Another object of the present invention is to provide a safety cap orplug device which is independently operated but can readily be attachedto the multiple outlet extension cord.

Another object of the present invention is to provide a safety cap whichis comparatively inexpensive to manufacture and can be readily assembledwith the safety cord at a minimum of cost.

Another object of the present invention is to provide a safety cap whichis frictionally retained within the outlet portions so that a smallchild cannot readily remove it from the extension cord.

With the above and other objects and advantageous features in view, myinvention consists of a novel arrangement of parts more fully disclosedin the detailed description following, in conjunction with theaccompanying drawings, and more particularly defined in the appendedclaims.

In the drawings,

FIG. 1 is a perspective view of a multiple outlet at the end of anextension cord equipped with the safety cap of the present invention.

FIG. 2 is a rear view .of the same.

FIG. 3 is a side elevation thereof.

FIG. 4 is a perspective view of the safety cap.

Small children are extremely curious. Especially babies at the crawlingstage have been known to push all types of objects into wall receptaclesand getting severely injured by the electric shock. To prevent this,safety plugs are used so that wall outlets not occupied with anextension can be closed up and sealed by means of a dielectric plug.These plugs are removable when it is desired to actually use the outlet.However, where extension cords are used to reach a lamp or otherappliance, the unused portions of the multiple terminal present the samehazards as the empty wall outlet. To this end, the present invention isdesigned to provide a safety cap which is readily mountable on anextension cord and is designed to plug up the unused portions of themultiple outlet so as to protect children from injury.

Referring more in detail to the drawings embodying my invention, FIG. 1illustrates a conventional extension cord assembly having a dual wireextending from a standard 3,339,367 Patented June 18, 1968 plug, notshown, for insertion into a wall socket, and a multiple female terminal11 mounted at the end of the cord 10. The terminal 11 and cord 10 areassembled in a conventional manner and preferably with the terminal 11molded of vinyl plastic material and molded to the end of the cord 10.The terminal 11 is of conventional design having a front wall portion 12with the pair of spaced terminal openings 13 for receiving the plug atthe end of the appliance or lamp. The center of the multiple terminal 11is provided with the transverse portion 14 having openings at each endto provide two additional spaces for receiving two additional plugs.These are the openings that are usually left open when only a singleappliance is attached to the front of the extension cord.

In accordance with the present invention I provide a safety cap such asillustrated in FIG. 4. This comprises a plastic, dielectric member 15molded in integrally connected flexible sections so that it can bemounted on the electrical cord 10 and extend over and into the opposedslots on the section 14 of the terminal. The member 15 is thus moldedwith a central rectangular comparatively thick portion 16 havingadjacent interconnected central openings 17 adapted to grip the cordlead connection 10 as shown in FIG. 2. A slot 18 extends from one sideedge and communicates with the portion 17 so that the member 15 can beslipped on to the electrical cord connection 10 by means of the slot 18which is tight but will give resiliently to permit a snap assembly.Adjacent opposite sides of the central member 16 are similarcomparatively thick plastic members 19 and 20 each integrally connectedto an edge of the member 16 by a thin flexible membrane 21. By mouldingthe plastic material thin at the portions 21 they will easily flexwhereas the members 16,. 19 and 20 are molded thicker and are morerigid.

At the outer ends, the member 19 is connected to another thick portion22 by an integral flexible web portion 23. The member 20 is connected toan end portion 24 by an integral flexible web portion 25. The outeredges of the portions 22 and 24 are tapered at 26 to provide a fingerengaging edge. The portions 22 and 24 are molded with integral elongatedrectangular tabs 27 extending at right angles from each side edge, seeFIG. 4. The width of the member 15 is such that the spacing between themembers 27 is approximately equals to the spacing between the plugopenings such as 13. However, the fit is tight, with the spacingslightly smaller so that the members 27 will grip the inside edge of theplug openings. This accentuates the friction between the two plasticelements, the member 11 and the member 15.

Now when the member 15 is mounted on to the cord lead connection 10 asshown in FIG. 2 with the cord extending through the slot 18 and into theOpenings 17, it will be found that pressure on the portions 22 and 24will force the members 27 into the opposed slots into the position shownin FIGS. 1 and 3. Since there is friction between the elements, somepressure is necessary and the parts will resist separation so that asmall child or baby will not be able to remove the safety cap 15. Theflexible connections between the members 16, 19, 20, 22 and 24 permitadjustment of the rear member 16 in sliding along the cord 10 'when themembers 27 are forced into the openings. This takes care of anyvariations in the length of the member 15 and allows manufacture withoutregard to close tolerances. If it is desired to use any of the crosscontact portions of the element 11, it is merely necessary to place thethumb or finger under the end 26 of either the topor bottom member 22 or24 and lift. the portion out of the particular cord plug openings. Inthis connection it should be noted that if one portion is lifted out theother one still remains in place so that each end of the safety cap canbe independently operated without disturbing the other end.

The cap 15 can readily be molded in a single piece at small cost. Toassemble it to the conventional cord lead connection it is merelynecessary to slip the cord through the slot 18. Therefore, the safetycap and its assembly adds very little to the general overall cost of theextension cord.

It should be noted that the safety feature of the cap of the presentinvention is concentrated in the end portions 22 and 24 with theextending tabs 27. The balance of the construction is designed to mountthe safety cap on the device so that it is always present and ready foruse. To this end the connecting portions 19 and 20 and even the rearpanel 16 may be made of thin flexible membrane or any other type ofconnection. The illustrated construction is designed to provide safetyplus strength so that if the device is stepped on or otherwise abused itwill not be dislodged or broken. Other advantages of the presentinvention will be readily apparent to a person skilled in the art.

I claim:

1. In an extension cord in which a length of two conductor electricalcord is provided with a contact plug at one end and a multiple tap atthe other end having a pair of flat longitudinal plug receiving slotsand a pair of fiat transverse slots adapted to receive a contact plug ateach end, a safety cap for said transverse slots comprising a dielectricmember mounted on said extension cord, and in which said dielectricmember comprises a plurality of fiat rectangular portions integrallyconnected by flexible webs, and means on said member for plugging theouter ends of said transverse slots when not in use.

2. A safety cap as in claim 1, in which one of said rectangular portionsis provided with a restricted slot for frictionally receiving saidextension cord to mount said member on said extension cord.

3. A safety cap as in claim 1, in which said means comprises spacedfla-t dielectric tabs extending at right angles from said member andadapted to frictionally enter and plug said transverse slots.

4. A safety cap as in claim 3, in which said member is provided with arestricted slot for frictionally receiving said extension cord to mountsaid member on said extension cord.

References Cited UNITED STATES PATENTS 1,978,510 10/1934 Spence 339-362,407,894 9/1946 Miller 33938 2,753,536 7/1956 Tjader 339103 3,275,9699/1966 Sheeran 339-103 FOREIGN PATENTS 465,837 6/1950 Canada.

MARVIN A. CHAMPION, Primary Examiner.

J. H. MCGLYNN, Assistant Examiner.

